package com.eminem.filter;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.io.IOException;

@WebFilter(urlPatterns = {"/user/*","/meet/*","/dept/*","/article/*"},dispatcherTypes = {DispatcherType.FORWARD,DispatcherType.REQUEST})
public class LoginFilter implements Filter {
    @Override
    public void init(FilterConfig filterConfig) throws ServletException {

    }

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest req = (HttpServletRequest) servletRequest;
        HttpServletResponse resp = (HttpServletResponse) servletResponse;
        HttpSession session = req.getSession();
        String sid = session.getId();
        //将登录用户id改成会话作用域的sid
        Object userId = req.getSession().getAttribute(sid);
        //id为空就是没有登录
        if (null == userId){
            //重定向回首页
            resp.sendRedirect(req.getContextPath()+"/index.jsp");
            return;
        }
        filterChain.doFilter(req,resp);
    }

    @Override
    public void destroy() {

    }
}
